<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style>
			.container {
				text-align: center;
				position: relative;
				width: 100%;
				background-color: #0099FF;
			}

			.item {
				position: absolute;
				width: 100px;
				left: 0;
				right: 0;
				margin: auto;
				background-color: #ff266e;
			}
		</style>
	</head>
	<body>
		<div class="container">
			<div class="item">居中</div>
		</div>
	</body>
</html>
